1,274 research outputs found
Improving the Accuracy of the Diffusion Model in Highly Absorbing Media
The diffusion approximation of the Boltzmann transport equation is
most commonly used for describing the photon propagation in turbid
media. It produces satisfactory results in weakly absorbing and highly
scattering media, but the accuracy lessens with the decreasing albedo.
In this paper, we presented a method to improve the accuracy of the
diffusion model in strongly absorbing media by adjusting the optical parameters. Genetic algorithm-based optimization tool is used to find the
optimal optical parameters. The diffusion model behaves more closely to
the physical model with the actual optical parameters substituted by the
optimized optical parameters. The effectiveness of the proposed technique
was demonstrated by the numerical experiments using the Monte Carlo
simulation data as measurements
Multispectral Bioluminescence Tomography: Methodology and Simulation
Bioluminescent imaging has proven to be a valuable tool for
monitoring physiological and pathological activities at cellular
and molecular levels in living small animals. Using biological
techniques, target cells can be tagged with reporters encoding
several kinds of luciferase enzymes, which generate characteristic
photons in a wide spectrum covering the infrared range. Part of
the diffused light can reach the body surface of the small animal,
be separated into several spectral bands using appropriate
filters, and collected by a sensitive CCD camera. Here we present
a bioluminescence tomography (BLT) method for a bioluminescent
source reconstruction from multispectral data measured on the
external surface, and demonstrate the advantages of multispectral
BLT in a numerical study using a heterogeneous mouse chest
phantom. The results show that the multispectral approach
significantly improves the accuracy and stability of the BLT
reconstruction even if the data are highly noisy
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